The Molecular Biology Core will support the various projects in this program by providing the following reagents and services: 1. Isolation and maintenance of shared pools of characterized osteoblast and osteosarcoma RNAs; northern blot analysis and nuclear run-on analysis as necessary. 2. Oligonucleotide synthesis. 3. Preparation and labeling of probes used routinely or in common by the projects. 4. Growth of recombinant DNA plasmids and phage. 5. Maintenance and permanent storage of plasmid, bacterial, and phage stocks (including bacterial hosts, vectors, libraries, etc.). 6. Preparation of plates and media for bacterial culture. 7. Construction of cDNA libraries. 8. Assistance with special projects, such as screening of cDNA and genomic libraries, or large DNA sequencing projects.